A FinFET is a transistor architecture of the metal-oxide-semiconductor field-effect transistor (MOSFET) type, which is favored as a replacement for planar MOSFET transistors in future integrated circuits fabricated in MOS technology, such as NMOS, PMOS, CMOS or BiCMOS.
A FinFET comprises a fin-shaped channel region that stands vertically on a substrate surface. The substrate surface is assumed as being oriented horizontally for the purpose of this description. In contrast to planar MOSFET transistors, which have a channel region in parallel orientation to the substrate surface, FinFETs allow superior channel charge control even at extremely short gate lengths.
U.S. Pat. No. 6,835,609 discloses a method of forming a double-gated SOI channel transistor comprising the following steps. A substrate having an SOI structure formed thereover is provided. The SOI structure including a lower SOI silicon oxide layer and an upper SOI silicon layer. The SOI silicon layer is patterned to form a patterned silicon layer. A dummy layer is formed over the SOI silicon oxide layer and the patterned SOI silicon layer. The dummy layer is patterned to form a damascene opening therein exposing: a portion of the lower SOI silicon oxide layer; and a central portion of the patterned SOI silicon layer to define a source structure and a drain structure. Patterning the exposed lower SOI silicon oxide layer to form a recess. Gate oxide layer portions are formed around the exposed portion of the patterned SOI silicon layer. A planarized layer portion is formed within the final damascene opening. The planarized layer portion includes a bottom gate and a top gate. The patterned dummy layer is removed to form a double gated SOI channel transistor.
US 2002/153587 discloses a double gated silicon-on-insulator (SOI) MOSFET is fabricated by using a mandrel shallow trench isolation formation process, followed by a damascene gate. The double gated MOSFET features narrow diffusion lines defined sublithographically or lithographically and shrunk, damascene process defined by an STI-like mandrel process. The double gated SOI MOSFET increases current drive per layout width and provides low output conductance.